Method of and apparatus for straightening violin bows



METHOD OF AND APPARATUS FOR STRAIGHTENING VIOLIN Bows Filed June 24, 1957 March 1, 1960 w. H. GENTILE 2 Sheets-Sheet 1 FIG. 3.

INVENTOR. WILL/AM H. GENT/LE "Wad MY ATTORNEYS United States Patent METHOD OF AND APPARATUS non SIRAIGHTENING vioLngBows William H. Gentile, Sacramento, Calif. Application June24, 1957, Serial No. 667,642 1 Claim. or. 144-261) violin bows, owing to their greater numbers and condi tions of use, are the kinds of bows most often found as requiring realignment.

Every bow, as it originally leaves the factory, has formed therein a curvature of predetermined are so as to exert a tension on the hair. When viewed from above the untensioned bow is linear; when viewed from the side, however, the untensioned bow is seen to have a sweep, the hair largely causing the sweep to disappear as tension is applied to the hair.

Undue exposure to the elements or accidental application of weight for any length of time to a portion of the bow frequently produces a set. or bend in or improper curvature to the bow. Furthermore, prolonged hair tension often results in a straightening of the bow. In either event, it is necessary in order to effect repair to realign or reestablish in the bow the proper curvature.

It is therefore an object of the invention to provide an inexpensive and quick yet accurate method of and apparatus for resetting bows to proper curvature.

It is another object of the invention to provide a generally improved process of a device for straightening bows used in connection with any of the stringed instruments.

It is yet another object to provide a method of and apparatus for establishing thecorrect curvature in any bow device, such as a cross-bow or long-bows used to propel arrows, for example. 1

Other objects, together with the foregoing, are attained in the method described hereinafter and in the embodiment described in the following description and shown in the accompanying drawings in which:

Figure 1 is an elevation of the straightener from the right side;

Figure 2 is a bottom plan;

Figure 3 is a longitudinal section, to an enlarged scale, of the torsion collar, the plane of section being indicated by the line 3-3 in Figure 1;

Figure 4 is a median longitudinal section, to an enlarged scale, of the torsion collar, the plane of section being indicated by the line 44 in Figure 2;

.Figure 5 is a top plan showing, alongside the straightener, a typical bow having an off-set curve to the right over a portion of its length;

Figure 6 is a view comparable to Figure 5 but with the torsion collar and the bow both inclined to the left at a predetermined angle; and

Figure 7 is a bottom view, to an enlarged scale, of the torsion collar end of the straightener, showing the bow in the straightener preparatory to heating.

r CE

While the method is capable of being practiced in several variant forms and the apparatus is susceptible of numerous physical embodiments, the process and device herein shown and described have been usednumerous times with eminently successful results.

The straightener, generally characterized by the uni meral 12, includes an elongated tube, 13 of a material conductivity, brass being having a substantial thermal very satisfactory.

The tube length and inner diameter will vary," at. In its pending on the types of bows to be handled. preferred form, the length of the tube approximates the length of the bow to be treated, whereas the inner and one-half inches. 1 r. i

To enable the user to determine accurately the location and extent of the misalignment on the bow a p111 rality of scribe marks 21 are etched on the tubing at,

regular intervals. Each of the scribe marks is further identified by one of a plurality of indicia 22, such as for example, the first number being 1, the second 2, etc.,

as appears most clearly in Figures 5 and 6, the numbers commencing at the upper or tip end 23 of the tube and progressing toward the lower or handle end 24 of the tube. Conveniently, the indicia 22 are scribed only on the upper or inside curved surface 26 of the tube. The scribe marks 21, onthe other hand, completely encircle the tube and therefore the scribe marks are also visible on the lower or outer side 27 of the curved tube surface, that is to say, on the surface of the tube most distant from the center of curvature.

In order to hold the bow at the required degree of angularity, a torsion collar 31 is provided. The torsion collar 31 comprises a sleeve portion 32 encompassing in rotatable relation a subjacent extension 33 of the tube 13. As shown most clearly in Figures 3 and 4, the collar 31 is prevented from upward translation by a bellmouthed or fiared portion 34 of the tube extension 33; downward translation of the collar 31 on the other hand, is blocked by an interfering shoulder 36 of a ring 37 secured to the tube 13 as by brazing 38.

The tip 41 of the bow, as appears most clearly in Figure 7, is snugly confined between a pair of scrolls 42 treme upper end of the bell-mouth 46 is provided with a bevel 47, the bevel 47 serving, in conjunction with the converging walls of the bell-mouth and the scrolls,

smoothly to direct the bow tip into fully lodged location:

as the bow is inserted in the collar and the tube.

A clamping mechanism, generallyde'signated .51 (Fig-- ure 1), enables the user to lock the collar 31 to the tube at any desired degree of relative angular displacement. A longitudinal slot 52 in the collar for approximately the lower two-thirds of the collar length is provided. A thumb-screw 53 passes through an unthreaded aperture Patented Mar. 1, 1960 a nearear 54, thence through and in threaded engagemeat w t the ead d o e i t a. a 56. finesse. from the near ear 54, the ears being mountedon the collar 31 and straddling the. slot 52. A shoulder 57 on the thumb. screw 53 bears against the. near eat 54 as the is taken'up. and urges the car 54 toward the ear 5.6, the slot 52, being narrowed accordingly, a powerful clamping effect beingthe result. I Appropriate indicia 61 on the ring 37, which is secured to the tube 13, indicate angular displacement of thecollar with respect to the tube, the collar slot 52 as an index, Diamet'rically opposite the slot on the opposite wall of the collar is an auxiliary collar index 62, as appears in Figures 2 and 7 whereas. an auxiliaryring index 63- appears on the ring directly opposite thecenter or base mark 64 (Figure 6) of the angular displacement indicia 61. Obviously, as the slot 52 is displaced in a given direction and amount from the rings center mark 64, the auxiliary collar mark .62 is displaced an identical amount, and in the same angular direction, from the auxiliary ring mark 63, allas is shown most clearly in Figures 6 and 7. This enables the user to know that displacement exists, ifit does, regardless of the,

position from which the straightener is viewed.

The manner of operation of the device appears in Figures 7. The user, having previously removed the,frog

(not shown) from threaded engagement with the handle or butt end 71 of the bow 72, places the frog and its attached hair73 slightly to one side, the other end of the hair. 73 still remaining attached to the bow tip 41 in the customary fashion. Straightening can be effected,

in other words, without detaching the hair from, the tip.

It will be assumed, for purposes of explanation, that through some mishap, thebow 72 is defective in that it has. abendor, curve 76 inv it for a portion of its length,

the; bend extending approximately between the upper.

location 77 and the lower location .78; furthermore the bend constitutes an arcuate. displacement to the right, as shown in Figure 5.

The user thereupon. grasps the butt end 24 ofv the straightenerand thebutt end 71 of the bowand places.

and.tlie. bow then takes mental note ofthe fact that the curve; extends. between the etched numerals l and 4 on the straightener and that maximum deflection occurs-approximately at a location. one fourth of the way from 2 toward 3.

The bow is thereupon inclined aboutits own axis so that the curved or bent portion of the bow is swung up wardly and tends to: disappear or merge into alignment with the rest. of the bow, as shown in Figure 6. This operationinvolves, with a right-hand bend, as shown, an inclination or tipping of the bow to the left, about-its own axis, approximatelythirty degrees orso, as appears in Figure6. Then, still holding the bow in canted attitude, the user rotates the collar '31 a corresponding amount andv in the same angular direction, judging by eye. When this. has been done, the collar is tightly clamped and the-bow is:inserted butt end-first in th'e'tube'and is pushed home -in such a'fashion that as'the bow isfully lodged the bow tip 41 is confined betweenithescrolls, as ap pears most clearly Figure 7..

At this juncture the bow is rather securely lodged within the tube and has been sooriented by the d isplaced collarposition thatthebent portion ofthe bow extending between the points 77 and 78 is opposed by the curvature of the walls of the straightening tube.

Thereupon, the user grasps the ends of the straightener and, holding the tube over an open flame, such as a Bunsen burner, moves thetube back and forth so that the flameplays over the tube between the mentally noted marks 1 and. 4 etched on the tube, with major play occurring in the portion between 2 and 3 where maximum bow deflection was previously observed.

Heating proceeds until the heated portion is no longer bearable to grasping of the fingers around the tube at the heated portion. The, tube and confined bow are, at this juncture, put aside and allowed tocool to ambient temperature. The bow is thereupon removed and will ducing curvature, the bow having been overly straightenedbyprolonged' hair tension, or other reason, the following procedure is followed. With the collar locked in middle or central location, as shown in Figure 5, the

bow is inserted in the straightener and pushed home so that; thetip 41 is lodged between the scrolls. The entire.

tube, rather than just a portion thereof, is heated over the burner until the tube surface is too hot to grasp. The straightener is thereupon allowed to cool to room temperature. After cooling, the bow is removed from the straightener. The bow, as itis taken out, is found to have set in. it the proper bow configuration and is ready to. have the. frog: re-placed and the hair tensioned. It has. been found asa final step that vigorous polishing, in a reciprocating longitudinal direction, with any of the betterstandard bow polishes serves not only to give the how an attractive appearance but also to set the bow fibers.

Itcantherefore be seen that I have provided a method.

lower side; said lower side being more distant from the center of curvature than said upper side, said tubebeing etched by aplurality of-equally spaced scribe marks disposed-along'the length of said tube, said tube also being etchedby a plurality of, progressively higher valued indicia each adjacent one of said scribe marks, a torsion collar encircling and rotatably mounted on saidtip end of said tube and extending beyond the end of said tube,

' said torsion collar including -a pair of spaced oppositely curled scrolls defining. a' pair of converging walls adapted References Cited in the file of this patent UNITED STATES PATENTS 50,272 Philbrook Oct. 3, .1865 198,780 Swartzet a1. Jan. 1', 1878' 1,376,678 Cua May 3, 1921 Bergmann Dec. 10,1929: 

